chemistry questio

an someone do a step by step of this pls

s part of an investigation, a student needed to prepare a buffer solution with a pH
value of 8.71. From the Ka value of phenol, the student thought that a mixture of phenol
and sodium phenoxide could be used to prepare this buffer solution.
The student decided to use a 0.200 mol dm–3 solution of phenol, mixed with an equal
volume of sodium phenoxide.
Use your knowledge of buffer solutions to determine the concentration of sodium
phenoxide solution that the student would need to mix with the 0.200 mol dm–3 phenol
solution.

ka =1.3 x 10^-10

Reply 1

charco

Study Forum Helper

Original post by ejfnewkjfoiwqbg

You know the target pH so you can determine the hydrogen ion concentration.

ka = [H+][A-]/[HA]

all components are in the same solution so you can work out the ratio of weak acid moles to salt moles by rearranging the equation.
Choose a random volume (say 1dm³) for the phenol solution so you have the moles of weak acid (phenol) so you can work out the moles of salt.
You can take it from there ...